Britney Spears Goes Naked, A** Up in New NSFW Video

Britney Spears' latest nude moment is seriously NSFW ... as she has put all of her assets on display for all to see.

The singer took to Instagram Wednesday evening, uploading a video of herself rolling around some crystal blue water ... totally nude. At one point, Brit lifts her butt into the air ... making the video even more suggestive.

The Grammy winner deliberately drew attention to her naked bee-hind, captioning her upload ... "Hello to my ass!!"

She chose the caption after previously writing on the post ... "Raised my ass a little higher so I have more booty!!! Thinking of getting injections on my ass to make it fuller like that."

We reached out to Meta to see if the post violates any guidelines. As of now, just like her ass, it's still up in the air.

Of course, this upload is just the latest in a string of concerning posts ... including a recent one where Brit railed about her relationship with her parents.

As TMZ previously reported ... Britney's mental and financial health is of deep concern for those in her orbit, especially after her physical altercation with her BF at the Chateau Marmont.

While some are calling for a new conservatorship, Dr. Drew says it's practically impossible to force the singer to get help.